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/*
* Copyright Jerome G. M. Benoit <jgmbenoit@rezozer.net> 2020
*
*/
#if !(__STDC_VERSION__ >= 201112L)
#error "require C11 or higher"
#endif
#include <sys/types.h>
#include <sys/param.h>
#include <stdalign.h>
#include <stdio.h>
int main() {
const char * ADHOC_ARCH_ENDIAN="";
const char * ADHOC_ARCH_SIZE_ALIGN="";
int is_bigendian=-1;
/* inspired by AC_C_BIGENDIAN */
#ifdef __APPLE_CC__
is_bigendian=0;
#elif (defined BYTE_ORDER && defined BIG_ENDIAN && defined LITTLE_ENDIAN && \
BYTE_ORDER && BIG_ENDIAN && LITTLE_ENDIAN)
# if BYTE_ORDER == LITTLE_ENDIAN
is_bigendian=0;
# elif BYTE_ORDER == BIG_ENDIAN
is_bigendian=1;
# else
# error "unexpected event"
# endif
#elif (defined _LITTLE_ENDIAN || defined _BIG_ENDIAN)
# ifndef _BIG_ENDIAN
is_bigendian=0;
# else
is_bigendian=1;
# endif
#else
/* From Harbison&Steele, section 6.1.2, ``Byte Ordering'' */
union {
long int l;
char c[sizeof(long int)];
} u;
u.l=1;
if (u.c[0] == 1) {
is_bigendian=0;
}
else if (u.c[sizeof(long int)-1] == 1) {
is_bigendian=1;
}
#endif
if (!(is_bigendian < 0)) {
if (is_bigendian == 0) {
ADHOC_ARCH_ENDIAN="le";
}
else if (0 < is_bigendian) {
ADHOC_ARCH_ENDIAN="be";
}
if (sizeof(void *) == 4) {
if (alignof(double) == 4) {
ADHOC_ARCH_SIZE_ALIGN="32d4";
}
else {
ADHOC_ARCH_SIZE_ALIGN="32d8";
}
}
else { /* (sizeof(void *) != 4) */
ADHOC_ARCH_SIZE_ALIGN="64";
}
}
printf("%s%s\n",ADHOC_ARCH_ENDIAN,ADHOC_ARCH_SIZE_ALIGN);
return 0; }
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